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SAFETY DEVICE FOR ELEVATORS. No. 577,649 Patented Feb. 23, 1897.

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Patented Feb. 23-, 1897'.-

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SAFETY DEVICE FOR ELEVATORS Patented Feb. 23, 1897.

Egg-5 town of Union, county of Hudson, and State as are used in oiiice-buildings, hotels, waredirection until all the doors or openings in the NITED STATES PATENT OFFICE.

WILLIAM EHRHARDT, OF UNION, HUDSON COUNTY, NEW JERSEY, ASSIGNOR OF ONE-HALF TO GEORGE A. OONNER, OF NEW YORK, N. Y.

SAFETY DEVICE FOR ELEVATORS.

.SPEGIFlIOATION forming part of Letters Patent No. 577,649, dated February 23, 1897.

Application filed January 4, 1895.

To all whom it may concern:

Be it known that LWILLIAM EHRHARDT, a citizen of the United States, residing in the of New Jersey, have invented a new and useful Automatic Electromagnetic Safety Device for Elevators or Hoistways, of which the following is a specification.

My invention relates to safety devices for hoistways, elevators, and elevator-shafts such houses, (lac.

The object of the invention is to provide means whereby it is made impossible to open the elevator-door when the car is out of proper position or to start the car until the car-door is closed and fastened, thereby removing the liability of accidents to persons attempting to enter or leave an ascending or descending car through a partially-closed door. Furthermore, the elevator cannot be started in either entire shaft are closed and fastened.

The attendants or operators of elevatorcars often open the doors leading to the car before the car has entirely reached the land ing and is still in motion, and passengers commence to leave or enter the car while it is still in motion. Many accidents of a serious nature have-occurred in this way.

Another object of the invention is to so construct the device that it will be exceedingly simple and may be applied expeditiously, conveniently, and cheaply to any elevator car and shaft.

To this end the invention consists in locating a brake-shoe or friction device above the highest point to which the car ascends in such a position as to operate against a brake-wheel fastened to the controller-rope pulley, said brake-shoe or friction device being brought into action and controlled by an electric current, the circuit of which is opened and closed by the opening and closing of doors at the various landings.

It further consists in providing the doors at the various landings with electromagnetic looks that are exceedingly simple in construction and which can be applied to any of the elevator-doors in a few minutes. These elec- Serial No. 533,866. (No model.)

tromagnetic locks are controlled by a boss fastened to the elevator-car. Arriving at a' floor-level, contact is made with a wall-spring placed in an electric circuit, whereby ahanging piece or pendulum, which is part of the electromagnetic lock, is attracted to the magnet and out of the path of the latch, which permits the latch to be raised and the door to be opened.

It also consists in a combination of these two sets of devices, whereby both the foregoing results are automatically accomplished.

It further consists in the novel construction and combination of the several parts, as will be herein after fully set forth, and pointed out in the claims.

By referring to the various drawings that accompany this specification, and of which they form a part, the manner of arriving at the above results will be seen and understood.

Figure 1 is a perspective view of an elevator-shaft with my invention applied thereto. Fig. 2 is a diagrammatic view of the same, and Fig. 3 is a detail.

Similar letters in the various drawings re fer to similar parts.

Fig. 1 illustrates an elevator or hoistway consisting of three floors, though I do not limit myself to any number of floors, as my invention can be used on elevators of from one floor up to any number of floors.

A represents the elevator-car, and it has arrived at the top or third floor.

At 13 is seen the shaft or well of the second fioor, the door being broken away to show frame O, which contains a spring or push-button D. The frame is fastened to the side of the well and the spring D projects through the frame 0.

At E is shown a pin in position to be struck by the door when closed, and at E a partof the framework has been removed to show the contact fastened to the pin and which is part of it.

F represents an electromagnetic look. a are the electromagnets; b, the hanging piece or pendulum, which is pivoted at c by a brass or non-magnetic pin and swings or rotates freely on said pin. When in its normal position, it hangs over the latch and prevents same from being raised, and consequently the door cannot be opened. Fastened to the side of the car A is a tapered boss or projection G. This boss is tapered at both ends, so it can rub against any spring it may come in contact with on either the ascent or descent of the car to which it is fastened. This boss is so placed that when the car has arrived at a floor-level it pushes in spring D, which closes an electrical circuit in which it is placed and of which it forms part. The electric current now flows around the electromagnets a, which energizes them, causing the hanging piece I) to be attracted and permits the latch to be lifted and the door opened. The hanging piece I) will be held in this position as long as the elevator-car remains on'a floor-level. At the upper floor in Fig. 1 the boss G is shown in contact with the spring D and the hanging piece I) is also shown attached to the electromagnet a by the induced magnetism due to the current passing around them. Fig. 1 also shows the door-pin E, which has been released by opening the door, and shows the contacts touching. Through these contacts an electrical circuit is made and the current energizes electromagnets I, placed at the top of the elevator-shaft. These electromagnets attract a lever J. To the opposite end of said lever is securely fastened a brake-shoe K. This brake-shoe K engages a brake-wheel L, fastened to the controller-rope pulley M, and prevents the controller rope from being moved as long as the door is open.

When the door is closed, the pin E will be flush with the framework of the elevatorshaft, the contacts at E will be separated, the electric circuit will be broken, the electromagnets will release the lever J, and the brake-shoe K, fastened to' the opposite end, will not be in contact with the pulley which is part of the controller-rope pulley M, allowing the rope to be freely pulled in either direction. If the door is not shut or only partly shut, the circuit will still be closed through the contacts shown at E and the attendant cannot operate the controller-rope. He must absolutely break the contact by shutting the door and opening the circuit through the contacts shown at E.

In Fig. 2 is shown the manner of making electrical connection with the electromagetic locks F. Pins E, embedded in the framework of the elevator-shaft and which are operated by the opening and closing of the elevatordoors and the wall contact-springs D, are shown in this figure. If there is an electrical plant in the building, a small continuous current can be shunted through these devices or an independent source of electricity, as, for instance, galvanic batteries, can be used. I prefer a three-wire system (shown in Fig. 2) for connecting up the locks and springs as one length of wire is saved. Two separate circuits can, however, be used, one circuit to actuate the locks and the other the brake device at the top of shaft, each circuit to have an independent set of batteries.

By referring to Fig. 2 my manner of con necting up will be clearly understood. N represents a source of electricity, as, for instance, a set of galvanic cells. A wire, No. 3, is connected to terminal cl of the cells and extends to the floor on which is situated the electromagnetic brake, and is connected to the wire 6 of the electromagnets. The other end of magnet-wire e is connected to the middle wire No. 2. One end of the wire-terminal of all the door-pins E is fastened to the wire No. 1 and all the other ends to wire N0. 2. Then a circuit is made by releasing any of the door-pins E, the current passes through the contacts into wire No. 2, up around the electromagnets at the top of the building and into wire No. 3, through the cells N, up through wire No. 1 to the springs. The current will flow through this circuit as long as a door-pin remains released.

In connecting the wall-springs I proceed as follows: I connect one terminal of all of the wall-springs D to wire No. 1. The other terminal I connect to one terminal of the electromagnetic lock located on the same floor. The other terminals of electromagnetic locks are all connected to wire No. 3. This completes the circuit from the cells through the wall-spring to the lock and back again to the cells.

Fig. 3 illustrates an electromagnetic lock with the cover removed. a a are the electromagnets. Z) is the hanging piece, 0 the nonmagnetic pin, and H the latch. In the drawings the latch is seen in the lock with the hanging piece I) over it in its normal position. This prevents the latch from being raised, and hence the door cannot be opened. When an electric current is made to travel through the electromagnets, the hanging piece I) is attracted to the magnets and remains in that position as long as the current continues to traverse said magnets. The dotted lines show position of hanging piece when attached to electromagnets. The latch can now be raised and door opened.

WVhat I claim as my invention, and desire to secure by Letters Patent, is-

1. The combination with the elevator-car and the shaft-door and its lock and startingrope, of a boss, as G, fastened to the exterior of the car, wall-springs, as D, fastened to the elevator well or shaft, electrical connections and a source of electricity, whereby said boss, when the elevator-car has arrived at a floorlevel closes an electrical circuit, rendering operative said lock and permitting the door to be opened, substantially as described.

2. The combination, with the elevator-car having a boss or projection thereon and the doors at the several landings, of electromagnetic locks, each consisting of a latch on the door, an electro magnet or magnets and a hanging piece or pendulum, and electrical connec IIS tions whereby the car, upon arriving at a floorlevel, causes said pendulum to be attracted to the magnet or magnets, permitting the latch to be lifted and door opened, substantially as described.

3. The combination of an elevator-car having a boss or projection as G, Wall-springs as D fastened to the well or elevator-shaft, a pulley around Which said rope passes, and a brake-Wheel fastened to said pulley, elevatorstarting or valve rope, and the doors at the several landings, of a brake-shoe as K, elec tromagnetic locks for the doors, each consisting of a latch on the door, and electro magnet or magnets, and a hanging piece or pendulum and electrical connections operated by the boss or projection fastened to the car to attract or release the hanging piece or pendu- 7 WILLIAM EHRHARDT.

Witnesses:

WALLACE W. THORN, JOSEPH P. EGAN. 

